As a prior-art air-conditioning apparatus applied to a multi air-conditioning apparatus for a building, an air-conditioning apparatus is proposed in which, for example, “(1) is a compressor; (2) is a four-way valve that switches a refrigerant flowing direction of a heat-source unit; (3) is a heat-source-unit-side heat exchanger; and (4) is an accumulator which is connected to the devices (1) to (3) and constitutes a heat source unit (A). (5) are three indoor heat exchangers; (6) is a first connection pipeline that connects the four-way valve (2) of the heat source unit (A) to a relay unit (E); (6b), (6c), and (6d) are first connection pipelines on the indoor unit side that connect the indoor heat exchangers (5) of indoor units (B), (C), and (D), respectively, to the relay unit (E) and correspond to the first connection pipeline (6); (7) is a second connection pipeline that connects the heat-source-unit-side heat exchanger (3) of the heat source unit (A) to the relay unit (E); (7b), (7c), and (7d) are second connection pipelines on the indoor unit side that connect the indoor heat exchangers (5) of the indoor units (B), (C), and (D), respectively, to the relay unit (E) and correspond to the second connection pipeline (7); (8) is a three-way switching valve that connects the first connection pipelines (6b), (6c), and (6d) on the indoor unit side to the first connection pipeline (6) or the second connection pipeline (7) side capable of switching; and (9) is a first flow-rate controller connected close to the indoor heat exchangers (5) and controlled by a superheat amount during cooling and a subcool amount during heating on the outlet side of the heat exchanger (5) and is connected to the second connection pipelines (7b), (7c), and (7d) on the indoor unit side. (10) is a first branch portion constituted by the first connection pipelines (6b), (6c), and (6d) on the indoor unit side and the three-way switching valve (8) switchably connected to the first connection pipeline (6) or the second connection pipeline (7); (11) is a second branch portion constituted by the second connection pipelines (7b), (7c), and (7d) on the indoor unit side and the second connection pipeline (7); and (12) is an openable second flow-rate controller that connects the first branch portion (10) and the second branch portion (11) of the second connection pipeline (7).” (See Patent Document 1, for example).
[Patent Document 1] Japanese Unexamined Patent Application Publication No. 2-118372 (page 3, FIG. 1)